Linking troubles: ideas requested ;-)

[Bernd Welter]

Hello together,

today I've been asked for a specific solution for the following situation - see attached image:

• customer wants to compute time of arrival based on current GPS position and next destination coordinates
• due to GPS deviation a vehicles on board unit provides the blue location as the current position - we also know that the vehicles heading is 181 (dotted line)
• what happens is that the vehicle is matched into a low level dead end street (purple icon)
• what we want to have is the vehicle being matched to the highway in direction 181 (red circle)

red circle = desired match location
purple icon = false match
blue icon = inaccurate position of GPS

linking troubles.png (20.45 KiB) Viewed 5864 times

We already played with the combination of standard properties coordinates, linking type and the non-standard heading (enabled in the profile, provided in the request) and this resolved another big issue but in this case we need a different approach.

Besides current (coordinates, heading) we also have access to a history of (coordinates, heading)... is there anybody who also tried to implement such a plot based on xRoute (and maybe xMapMatch)?

I need an ignition spark

Best regards Bernd

[Joost]

The proper way would be to feed the last few points of the track into xMapmatch and do a global matching. If this is doable and how big the trace needs to be depends on the quality of the signal.

Off coarse there is also the "shadey" way: install an extracted instead of detailed map. If there are no small roads in the map, the xRoute cannot link to them .

[Bernd Welter]

Hello Joost,

I think we have to evaluate the usage of xMapMatch because under some special conditions it is definetly necessary to link the GPS to the low level street - if the recent coordinates seem to belong to that kind of street after the map matching.

Using a poor map with high level streets is definetly not a valid approach, e.g. because the destinations of the users could also belong to low level streets and we need a precise routing.

Best regards and one more time "thanks for the input",

Bernd